Why no temp probe? I think EdSett has covered the multiple failure issue above - seems a reasonable explanation as to why there isn't a case for fitting one. Sounds logical to conclude the risk probabilities are just too low - and if you are spending money, its better spent elsewhere on higher risks to the aircraft. Does this argument make sense to those calling for one to be fitted? If not, why not?
Also...
I think that you can at least be pretty confident that the Type Approval from the DoT means that your car was constructed in accordance with UK vehicle regulations and that, for example, fuel lines will not be placed above exhaust pipes so that a clip failure would not allow the former to impinge on the latter with disastrous results.
...these are the same regs I take it that failed to prevent Audi from selling 1000s of cars which killed at least 5 people before they were all recalled for safety related modifications (Audi TT, circa 2000). There appears a blind belief that only military airworthiness is bad, everything else good. Why such a bitter blinkered view - couldn't get promoted?